The present invention relates to a liquid ejecting device, a printing apparatus and a liquid supplying method capable of supplying a liquid stored in a main tank to a head through a sub-tank.
As a liquid ejecting device, there is known a device that is mounted in a printer connected to a personal computer or the like and supplies ink as liquid to a print head.
Such a liquid ejecting device includes a sub-tank unit that is mounted in a carriage and receives the ink in an ink storage chamber through an ink supply tube from an ink cartridge to supply the ink stored in the ink storage chamber to a print head at print time; a pump unit that supplies the ink of the ink cartridge to the sub-tank unit; and a pump control unit that controls an amount of the ink in response to a driving signal transmitted to the print head (for example, see Patent Document 1).
However, the pump unit has a complicated structure and needs a large installation space. In order to achieve a simplified and miniaturized structure, an ink supplying device that supplies ink using a driving force of reciprocation motion of a carriage is known (for example, see Patent Document 2).
As disclosed in Patent Document 2, the ink supplying device includes a carriage that reciprocates, an ink cartridge that stores the ink to be supplied to an ink jet print head equipped in the carriage, and an ink storage unit that stores the ink to be consumed upon performing printing by the ink jet print head. In addition, the ink supplying device further includes an ink pump unit that supplies the ink to the ink storage unit when compressed by movement of the carriage toward a predetermined position and sucks the ink from the ink cartridge when restored by movement of the carriage toward a position out of the predetermined position.    Patent Document 1: Japanese Patent Publication No. 2001-270133 A    Patent Document 2: Japanese Patent Publication No. 2007-160639 A
However, the ink supplying device that compresses the ink pump unit with the driving force of the reciprocation motion of the carriage includes the ink storage unit that is a separate tank as a buffer for storing the ink supplied from the ink pump unit. Therefore, a problem occurs in that the size and cost of the ink supplying device may increase.